The disadvantage of the car kettle is that if the power of the car kettle is too large, it is easy to cause a short circuit in the car and burn the fuse. If you use the car kettle, you must start the engine, because the car kettle will increase the burden on the battery, and if you rely on the battery for a long time, it will easily damage the battery. The engine must be in the starting state to prevent the battery from being damaged due to power failure.